8 3/4 MP bearing set

[xf69fs]

I need new bearings for my 8 3/4, as well as flanges. It is an adjustable bearing/flange setup. Would the MP non adjustable bearing setup work? Anyone with any experience with these?

[tsteiner61]

I recently converted from adjustable to non-adjustable (Green) bearings on my 8 3/4.

There is only one problem with the conversion, but it is a BIG one.

At the very center of your pumpkin is a metal spool about the size and shape of a standard thread spool called an adjuster spool or axle spacer. It's function is to provide a conduit between the axles so that you can adjust the whole setup with the single adjuster.

When running Green bearings, this MUST be removed. If you do not remove it, both axles will no longer fit in the case. When you press one in, the other will pop out.

The Problem: taking this thing out requires pulling the pumpkin out of the case. Something I don't know that you'd want to do for a simple bearing swap. It's a good deal more work.

Somewhere in the archives I have a thread where made the mistake of not taking out the spacer. If you can find it, it's pretty funny stuff.

[xf69fs]

How hard is it to get this "spool" out? I have had the 3rd member out already, I opened it all up when I got it. Yea my story is pretty funny to why i need new bearings...one axle is about 1/2 inch longer than the other....i put the wrong axle on the wrong side and bent the flange. So i somewhat fixed the flange, and reversed axles. But the adjuster got messed up in the whole thing so we (my dad and I) somewhat adjusted it and then welded the adjuster....turns out it wasnt all the way adjusted. So my alxes had a little bit of sloppyness to them, and it was leaking gear oil form the seal, I swear i spent 100 bucks on new ones. So i just said F*** this! I now am running aorund with a 7 1/4 till i get my 8 3/4 back up.

[tsteiner61]

IMO, it's a BIG PITA, but I tend to be lazy.

Your 3rd member is out, but I'm going to have to assume it's still together. (Bearing caps still on, backlash set, etc. There's no getting to this thing unless you remove the pumpkin (ring & case) from the rest of it. I believe that unless you are super careful in doing this, you will have to reset at the very least your backlash, which I found tedious.

Then you have to hope you have an older unit. (I still can't figure out how to open and service the newer Auburn units that MPP is shipping now.)

The picture below is of an older model, distinguishable because it has two circles of bolts rather than just one like my new one did. OK NO PICTURE since this feature isn't working.. You basically have to tear the pumpkin in half by removing the entire inner circle of bolts (the outer circle is for the ring gear of course), punch out the pin, and just slide it off the shaft. Be careful when you do this as the internals fell all over the floor on me before I had a chance to make a mental note of where they went. The spool will be attached to shaft for the two smaller gears. Slide off the gears, punch out the pin, slide the spool off and put it back together.

Hope this helps.

[xf69fs]

Crap I didnt need to hear that. Its a 69 A body rear end, so its old, yes its in one piece right now.... Would it be possible to ahve the ends of the axles shortened? Cause i really dont want to rip it apart, unless i can find a rear end that had the green bearings to begin with??

[tsteiner61]

There is really no good way around this, but I will share with you some things I have tried and the results.

1. Shim the difference with gaskets. Make sure to use the good felpro copper kind rather than paper or cork, as now the gaskets will be absorbing some of the lateral load the axle creates when you punch the throttle. With this method, I recommend not going any thicker than 6 gaskets (.015" each compressed for felpro copper total .090") on each side. And I would torque the flange nuts down about 5-10 ft./lbs. tighter than spec.

2. Better. Shim the difference with plate metal. Now you won't have to worry about stability at the axle flange as much. Make sure to put a gasket on each side of each plate (2 plates, 4 gaskets.) And don't forget to take that into account when measuring.

3. Best. Bite the bullet and do it the right way. I know that suc#s to hear, I was in the same boat, but to be honest getting the measurement right is a pain, and if it's not accurate, you risk either throwing the axles out of the case (axle splines not far enough toward center), or burning up the inside of the case (splines too far toward center).

Sorry not better news.. but...

[JoeMack2]

Hey TSTEINER61, I've got an 8 3/4 (489 case, sure-grip) in my 68 Satellite which I converted over to the green gearings. I did not know about the spacer that you described so I guess it is still in there. Everything went together OK and I have been driving the car like this for about a year and have had no problems. Are you sure that all 8 3/4 rears have it and that it needs to be removed if switching over to the green bearings? Just wondering.

[xf69fs]

So are the bearings worth it? I can get the adjustable ones through Year One, but they are 90 bucks per side vs 125 for the MP set. I can install them, and if i ahve to remove the spacer thingie in the gears, so be it.

[tsteiner61]

xf69fs,
From what I've experienced, you're not really getting a performance upgrade in switching over to the Greens, just the ease of not having to adjust the axles upon installation. Given what I went through, I would stick with the stock adjusting set. If only for the simple reason that you KNOW it will fit. With the Greens, maybe they fit, maybe they don't. BTW, Mancini Racing sells Greens for $84.95 (800-843-2821), $120 is a little much.

JoeMack2,
I just assumed all 8 3/4s would have this problem because mine did. Problem is I don't know what type of car it came off of, because it was on my B100 van when I bought it, but these vans never came with that axle. I would guess it to be a truck rear due to the location of the leaf spring pearches (top vs. bottom). Plus I've heard other members having the same problem, because they are the ones who alerted me to this issue when I posted with the same problem about 3 months ago (I think it was a70Duster). The post is probably gone though due to the recent server crash. And I am pretty sure that all units come with this spacer, otherwise you wouldn't be able to adjust both axles with only one adjuster.

[dusterbd]

im having this same problem with my moser axles and green bearings. i called moser for correct installation procedures, and they said to make sure i wasnt drawing the axles in with the plates. if i was, take a grinder or chop saw and shorten the axles. this seems kida sketchy to me. but thats what they said to do. what i want to know is, is there a way to check for clearance between the axles and this pin? if so, how do i do it? this would save both me and xf69xs a lotta heartache, as it would tell us wether or not the interference affects us. thanks.
mike

[tsteiner61]

Whatever you do, don't start chopping up your axles.

Unfortunately guys, there is no good way to check that I know of other than to just bolt one axle in then try the other. It will either fit or (more than likely) it won't.

I spent 6 agonizing weeks going through the same ordeal with mine. Let me tell there are only two correct options, neither good.

1. Bite the bullet and take out that spacer spool. This is the correct way to do it. It will most likely mean you will have to reset your diff. back to spec (a really big PITA, IMO).

2. Switch back to regular bearings. Everybody is hyping the Greens, but I really don't think there is any difference in performance. It's just supposed to be an ease of installation thing. But obviously it's not easy unless you have taken out that spacer before you even start.

The only other option (see above) is to shim it at the flange. But this really isn't the optimal way to go. More just an idea.

Sorry not better news. Maybe someone else here on the board knows a better way. Guys???

[xf69fs]

The main reason I am asking about the bearings is because i HAVE to get new ones, mine are totally f***ed. Its 125 for the green set and like 180 for the adjsutable set through Year One. Being that they may not fit, I might spent a lot more and get new adjuatable ones...

[tsteiner61]

xf69fs,
When I say 'switch back' to regular bearings, I was more talking about dusterbd's case where he already has the Greens on. In your case that would be get new adjustable rather than Greens. They may cost more, but it's a GUARANTEED fit. With the Greens, there's no way to tell until it's too late.

I would shell out the extra cash for the stock stuff. The peace of mind is worth $55 in my book. Just my opinion.

I've personally had this happen to me (Greens not fitting right) and it turned a weekend project into a six week headache.

[mauve66]

just read the onfo on the adjustables being put in the wrong side. Mine gear was replaced three years ago by a drivline shop and I just took them out to install rear disk brakes and found out that they put them in wrong, one side was leaking, and they threw away the adjuster lock thingy. I replaced the seals, bearings looked good so I just repacked them but when I put the axles back in the proper side the adjuster would NOT turn at all. The axle setting is pretty close to where it should be but without the nut lock thingy am I wasting my time?? Is the adjuster wasted since it won't turn in either direction??? Any help thanks

[xf69fs]

mauve66,
You could go to a wrecking yard and get the adjuster clip, or get whole new flanges form Year One. I still may go that road if I decide not to go disc brakes on my rear end.

[cudacarl]

I have the Green Bearings In Both My 'cuda and my Magnum (which has a rear from a '73 roadrunner). I never knew about removing anything so i just bolted it all together and it all worked fine. That waas about 6 years ago. About 5 years ago my cousin put them in his '73 challenger w/440 . He beats the hell out of that car and hasn't had any problems either. All rears 8 3/4. One thing i did do was make sure i had the axel with the threads for the removed adjuster installed on the drivers side like it used to be.

[mauve66]

the only places I've seen out here carry late 70' - early 80's stuff which would be 7.25 I think. Do all of the axles have this clip or do I need to find an 8.75 under something??? Is the adjuster flange the same for all axles or just for the 8.75??

GET REAL GET MOPAR or GO HOME
little boys wear bow ties, flat heads are for nerds

[cudacarl]

My magnum had 8 1/4 rear originally and it didn't have those adjusters. You might be able to get the clip from year one. The reason i used the green bearings was the threads on the axel had worn away so the adjuster got mashed in the axels end play. You may want to look and see that your threads are o.k.

[George G. Leverette]

Read all of the posts on the non-adjustable axles and some are confusing. I have converted several cars to the non-adjustables with conversion axles cut by Sutton Engineering in SoCal and had the bearings installed. The cars are \6, 440 Duster, 340 Duster and 68 Cuda with some E and B-bodies from friends cars. Never heard of or experienced any problems, just install the pumpkin slip the axles in any side tighten it up, and add Mobil 1 Synthetic fluid and forget the rear end.